Dear Dr. Roach: I am a 70-year-old male who is 6 feet, 3 inches tall and weighs 190 pounds. Other than having high blood pressure, I am healthy, eat a Mediterranean-style diet, and exercise most days. Since 2021, I have been taking one tab of amlodipine/valsartan daily with blood pressure readings of 125-135 / 70-80 mm Hg and a heart rate of 55-60 bpm.

At my recent visit, I was found to have a high potassium level of 5.5 mmol/L. For two weeks, I stopped eating bananas and also stopped taking my multivitamin, and my potassium level slightly came down to 5.2 mmol/L.

My questions are: Is the high potassium due to my diet or medication, and do you think my blood pressure is in good control?

— E.S.

Answer: Valsartan, which is in the class of blood pressure medicines called the angiotensin receptor blockers, typically does increase blood potassium levels, so 5.5 mmol/L is not an uncommon level for people who take this class of medicines.

Nobody likes to see an asterisk next to their test results that indicates something abnormal, and many people know that high potassium levels can be dangerous. So, I understand why you are nervous. However, the decision to change or reduce the dose of the medicine must be based on your individualized case.

The first step is to have a low-potassium diet. Bananas and citrus fruits and juice are among the biggest sources of potassium in the diet. However, these are also healthy options, so I don’t always advise stopping these entirely. I recommend keeping them down to reasonable amounts (such as one whole fruit daily).

Although some authorities do recommend changing or stopping these drugs with moderately high potassium levels like 5.5 mmol/L, I personally tend to avoid doing so. These drugs are effective and have relatively few side effects.

Furthermore, studies using these drugs in people with heart failure (in combination with a diuretic that also increased potassium levels) found that there was little to no risk when the potassium level was below 6 mmol/L — a level where most physicians become nervous.

A study in people whose kidney function wasn’t perfect (putting them at a greater risk for high potassium) and who took these medications found that stopping them led to worse outcomes, such as heart attacks and strokes.

My policy is to carefully consider the options, and if the medication has significant benefits for my patient, I will usually keep them on it and monitor them carefully with modest changes in their diet. They should also avoid salt substitutes, which are loaded with potassium, and be careful with medicines like ibuprofen, which can worsen kidney function and cause high potassium.

Dr. Roach Writes: After I printed a recent column on the risks of potentially cancer-causing, fire-retardant chemicals in black plastic, an error was reported by the authors of the study. They had miscalculated the amount of toxic chemicals per body size, leading to a tenfold overestimate of concentration of these dangerous chemicals.

Many readers asked me to print this follow-up and note that the conclusion of the paper shows that the risk from these chemicals probably isn’t high.

Contact Dr. Roach at ToYourGoodHealth@med.cornell.edu.